In a great example of serendipity, the talking to myself is a case. I was observed doing that and people thought it would be weird, so I stopped doing that.

When I was younger, some adults told be that "you only understand something when you can teach it to someone", which people in my circle disputed as they were the kind of people that like to think of themselves as smart.

I didn't go to a couple of parties to socialise because there were people drinking copious amounts of alcohol, because there was a stigma against getting drunk and stupid. While the not drinking certainly was a good idea, the not socialising was not.

As a child I was extremely interested in everything scientific. Then in school none of the cooler kids were and neither were the friends I actually had, so I started playing video games. Thankfully I later found people interested in scholarship so I started doing that again.

(I am starting to realise most of these are from when I was in school. Might be because I matured or because I have more perspective through the distance)

Not that peer pressure can't have good effects, it is a tool like any other.